As a compressor which is a type of rotary machine, there is an axial flow compressor. The axial flow compressor is provided with a rotor rotating about an axis, a casing which covers the rotor allowing the rotor to rotate, and a vane ring formed in an annular shape about the axis and provided on an inner circumferential side of the casing. In this type of axial flow compressor, from the viewpoint of ease of assembly and the like, the casing is able to be split into a top casing and a bottom casing, and the vane ring is also able to be split into a plurality of vane segments in the circumferential direction. In the top casing and the bottom casing, vane ring grooves depressed from the inside in the radial direction toward the outside in the radial direction and extending in the circumferential direction are formed. Each of the vane segments is mounted in the vane ring groove of either the top casing or the bottom casing.
In a case of inspecting and repairing the inside of the rotary machine as described above, it is necessary to detach the top casing. Therefore, Japanese Unexamined Patent Application Publication No. H10-317912A discloses a method in which an upper casing (top casing) is detached from a lower casing (bottom casing) and inverted, and the inside of the upper casing of which an opening faces upward is inspected and repaired.
In addition, Japanese Unexamined Utility Model Application Publication No. H4-109820U discloses a method in which an opening of a casing split in half is made to face upward and a vane segment is drawn out to the upper side from the casing using a chain block or the like.